Antenna support



Oct, 22, 1929. o. MARSTELLER ANTENNA SUPPORT Filed Sept. 2, 1926WITNESSES:

UNITED STATES lhlE Tlflt 0. MABSTELLIER, OF PITTSBURGH,

HU'U3E ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYL VIA.

PATENT PENNSYLVANIA, ASSIGNOR T WESTING- ANTENNA ETUPPORT Applicationfiled September 2, 1926. Serial No. 133,114.

My invention relates to antenna supporting devices, and it hasparticular relation to devices designed to rotatably support loopantennae.

a (The object of my invention is to provide a loop-antenna support thatmay be turned irrespective of an accumulation of ice thereon.

Another object of my invention is to provide a loop-antenna supportparticularly n adaptable for use in connection with direction-findingequipment on shipboard, at land stations, on dirigibles, or onaeroplanes.

The use of loop antennae in connection with radio direction-findingequipment on ship- 1185', board becoming practically universal. Theseantennae are usually mounted either on the deck of the ship, or on theroof of the cabin containing the radio apparatus, where they are freelyexposed to the weather. It is aa customary to protect the conductorsconstituting the loop by a Water-proof shield of dielectric material toprevent moisture from.

altering the constants of the loop, but in so far as l am aware nospecial eflort has been made to design a loop-supporting device thatpermits an unimpeded turning of the loop under conditions causing anaccumulation of ice at the location where the loop is mounted.Obviously, if the loop is to be constantly available, it is necessary toprovide means whereby moisture is prevented from congealing around thepoint where the Vertical loop-carrying shaft passes through the deck orthrough the roof of the radio cabin.

l have accordingly designed a loop-supporting bearing provided withwater-proof protecting means, and in addltion haveprovided a heatingdevice to prevent the accumulation of ice between exposed portions ofthe protecting means.

The novel features which I consider characteristic of my invention areset forth with particularity in the appended claims. The inventionitself, however, both as to its organization and method of operation,together All with further objects and advantages thereof,

will best be understood by reference to the following description takenin connection with the accompanying drawing, in which,

at Fig. 1 is a perspective view of a ships radio cabin, showing themanner in which my invent on is applied to the vertical shaft supportinga loop-antenna for rotation, and Fig. 2 is an elevational view, partlyin sect on, showing a preferred form of my invenion.

Referring to Fig. 1, a radio cabin, or deckhouse 1, has a shieldedbearing device 3 mounted on the roof 2 thereof, through which passes avertical shaft 4: carrying a loop-antenna 5 at its upper extremity. Thevertical shaft may be turned by hand-wheel 6 and a suitable train ofgears '1, if desired.

In order to simplify the illustration, additional radio apparatus hasnot been shown.

Referring to Fig. 2, the hollow shaft 4, at

the point where it passes through the roof,

may be constructed as shown in the drawing,

in which the vertical downward thrust of the shaft caused by its weightis carried by a plurality of balls 8 rotatable between an upper race 9affixed to the shaft and a lower race 11 supported by a circular member12 affixed to the roof. A plurality of retaining rings 13 provided withopenings maintain the balls in proper spaced relation circumferentially.

A similar bearing 14 surrounds the shaft immediately below the point atwhich it passes through the roof, in order to give rigidity to thesystem and prevent unseating of the shaft when exposed to heavy windsand seas.

A conical skirt 15 surrounds the lower portion of the shaft 4, and isaffixed to the roof by a plurality of bolts 16. A gasket 17 of felt orother analogous material, inserted between the lower edge of the skirtand the roof, prevents the access of water to the bearings.

Another conical skirt 18 is aflixed to the shaft 4 by means of bolts 19,and is so arranged that the flaring portion 21 thereof encircles theupper portion of the skirt 15 which is affixed to the roof. lit is notneces-' sary in all cases that the skirt 18 be affixed to the shaft, itbeing obvious that if the shaft does not rotate that this skirt shouldbe afllllll ture. A packing ring 22 may be interposed between the shaftand the small end of the skirt 18, if necessary to prevent the ingressof moisture.

A ring 23 of water-proofed felt or analogous material is carried on theinterior surface of the flaring portion 21 of the upper skirt, beingaflixed thereto by a plurality of bolts 24, or by other means. Thisring, which makes contact with the lower skirt, and effectually closesthespace between it and the upper skirt, is impregnated or treated toreduce friction and exclude moisture.

Another ring of water-proofed felt 25 is carried on the exterior surfaceof the upper end of the lower skirt, being affixed thereto by aplurality of bolts 26. The bolts 26 may also be utilized to support aninterior ring 27 adapted to fill the space between the upper end of thelower skirt and the shaft.

A heating device, illustrated as a steam coil 28, is arranged around thelowerportion of the shaft, between it and the skirt carried by the deck.This device prevents the accumulation of ice between the lower portionsof the two skirts, and at the same timemaintains the lower skirt at atemperature sufficiently high to prevent the lower felt ring 23 fromfreezing thereto.

Theupper felt rings 25 and 27, being protected against moisture, neednot be heated except incidentally by heat conducted to them through thelower skirt.

If desirable, electric heating means preferably comprising anon-inductive resistance coil may be substituted for the steam coilillustrated. An inductive coil might also be used, since the skirtsconstitute an effective shield which may be grounded if necessary.

In the operation of my device in extremely cold weather, and underconditions tending to cause an accumulation of congealed moisture aroundit, the loop may be rendered freely rotatable merely by energizing theheating means. Any ice which has accumulated between the lower portionof the upper skirt and the lower skirt is immediately melted, andcontinued application of heat prevents the further accumulation thereof.Heat is conveyed by conduction through the material of the lower skirt,to all parts thereof, and any ice that has accumulated between theskirt 15 and the lower packing ring 23 is melted, as is also any icethat may possibly have formed between the upper inside ring b 27 and theshaft 4. Inasmuch as the upper inside ring is very thoroughly protected,ice is very unlikely to accumulate thereon, though in extremely severeweather this accumulation is possible.

It is thus apparent that by my invention I have provided an extremelyefficient protective device to be used with loop antennae mounted inexposed positions. The device may be applied, without great expense, toantenna-supporting shafts already in use, although I consider itpreferable to construct the shaft, the bearing, and the protectivedevice as a unit.

In addition to preventing the accumulation of ice from preventingrotation of the antenna-supporting shaft, a device constructed accordingto my invention adds appreciably to the rigidity of the structure.Bending moments occasioned by heavy wind or by the pitching of thevessel are transmitted from the shaft to the lower skirt through themedium of the water-proofing rings, and are prevented from causing unduestrain on the main supporting bearings. The reception of radio signalsis also improved by the elimination of vibrations in the supportingshaft which tend to affect the inductance and distributed capacity ofthe loop, and disturb the tuning thereof.

In order to clearly disclose an operative embodiment of my invention, aspecific form thereof has been illustrated and described. I am fullyawarethat many modifications will be obvious to those skilled in theart, and my invention is accordingly not to be limited except as isnecessitated by the prior art and by the spirit of the appended claims.

I claim as my invention:

1. In combination, a shaft adapted to carry radiant energy receivingmeans, a bearin in which said shaft is mounted for rotation, bearingsupporting means, shielding means for said bearing affixed to saidbearing supporting means, additional shielding means carried by saidshaft and cooperating with the fixed shielding means, andwater-resistant packing devices interposed between said shielding means.

2. In combination, a shaft mounted for rotation in a bearing carried bya supporting device, fixed shielding means carried by said supportingdevice for preventing the access of moisture to said bearing, additionalshielding means carried by said shaft and cooperating with the fixedshielding means, heating means for preventing the accumulation ofcongealed moisture at the location where the two shielding meanscooperate, and water-resistant packing devices interposed between saidshielding means.

3. In combination, a shaft adapted to carry radiant energy receivingmeans, a bearin in which said shaft is mounted for rotation, earmgsupporting means, a frustro-conical shield carried by said bearing suporting means arranged to encircle sald s aft and protect said bearingagainst the access of moisture, an additional frustro-conical shieldencircling said shaft and lying in nested relation with the firstmentioned shield, and packing means between said shields.

4. In combination, a shaft adapted to carry radiant energy receivingmeans, a bearing in i vaa eea "which said shalt is mounted for rotation,a shield encircling said bearing and shaft an additional shield carriedlo said shaft encircling and ccvering said rst shield, packing meanshetween said shields, aoking means hetvveen said first mentioned shieldand said shaft, and means for applying heat to said first shield. 1

5. ln combination, a shaft adapted to carry m radiantfenergy receivingmeans, a bearin in Which said shaft is mounted, for rotatlon, means forapplying heat to said bearing for the prevention of ice accumulations,and means for preventing electro-magnetic diss tnrloances originating insaid'heating means from aflecting said receiving means. 7

lln testimony whereof, I have hereunto subscribed my name this 10th dayof August, 1926. ii

. an LESTER O. MARSTELLER.

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